Memories may be included in a variety of apparatuses, such as computers or other devices, including but not limited to portable memory devices, solid state drives, personal digital assistants, music players, cameras, phones, wireless devices, displays, chip sets, set top boxes, gaming systems, vehicles, and appliances. Memories may be volatile, where power is needed to store date, and non-volatile, where data is stored even if power is not provided to the memory, or combinations of volatile and non-volatile memory. There are many different types of volatile and non-volatile memory including random-access memory (RAM), read only memory (ROM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), flash memory, and resistance variable memory, among others.
Memories, such as resistance variable memory devices, may be used as non-volatile memory for a wide range of electronic devices. Resistance variable memory devices may include, for example, phase change memory (PCM) or resistive memory, among others. In some instances, it may be desirable to use PCM to implement random access memory. As a result of the limitations of using PCM as RAM replacement, operation of PCMs in memory systems may be restricted and/or require additional mechanisms for operation. For example, blocks of PCMs may be limited to a relatively low number of write operations compared to RAM and may require additional housekeeping mechanisms (e.g., wear leveling operations, refresh operations) to ensure feasible RAM replacement.